The present invention relates to an ultrasonic picture processing method and an ultrasonic picture processing apparatus for determining and collecting pictures which are important to the diagnosis of a disease and which are not affected by the movement of a subject's body and by the movement of inspector's hands, from ultrasonic pictures obtained by an ultrasonic diagnosis apparatus, and to an ultrasonic picture processing apparatus.
The present invention also relates to an picture processing apparatus for extracting the contour of a target and displaying a picture capable of determining whether or not the extracted picture is fitted to the target.
In recent years, as people's eating habits are improving, the number of people suffering from diseases such as obesity and hypertension is increasing in Japan. Since the mortality rate of cardiac diseases resulting from these diseases is a second highest next to cancer, they are becoming more and more serious problems. In the diagnosis of a cardiac disease, an electrocardiogram is used as a primary diagnosis method. For further detailed picture-using diagnosis, diagnosis using an ultrasonic diagnosis apparatus is widely applied due to convenience and low cost (compared to other diagnosis apparatuses such as X-ray CT, MRI and PET).
When diagnosing of a cardiac disease using the ultrasonic diagnosis apparatus, real-time moving pictures obtained by the apparatus are used in most cases. A doctor observes the movement of the cardiac wall of a patient for one piece of diagnostic information and diagnoses whether the patient's heart is abnormal. In case of a cardiac disease such as cardiac infarction and stenocardia, the abnormal movement of the cardiac wall is observed. It is desirable that such observation is conducted while parts other than the to-be-observed heart are static. This is because it is necessary to find out an abnormally moving region within the incessantly moving cardiac wall and to make a precise diagnosis.
Meanwhile, in case of an picture diagnosis by using the ultrasonic diagnosis apparatus, a system for collecting pictures by applying an ultrasonic probe to a subject is adopted. In this system, not only the patient but also the ultrasonic probe is not fixed and it is possible to freely change an observed region. Such a system is advantageous in convenience and the degree of freedom. However, if the movement of the heart is observed using this system, pictures tend to be blurred due to the movement of the subject's body and the movement of the inspector's hands. Even if pictures are collected while carefully preventing the blur of pictures, it is not clear whether or not pictures not blurred and suited for diagnosis can be obtained and the inspector needs to determine whether or not the pictures are appropriate. This determination lacks objectivity and causes an increase in the burden on the inspector. Such a system cannot expect effective diagnosis and may increase diagnosis time.
As described above, if making a diagnosis of a heart by using the ultrasonic diagnosis apparatus, it is necessary to pay attention to collecting blur-free pictures suited for diagnosis. The determination whether blur-free pictures have been obtained depends on the inspector, which disadvantageously lacks objectivity and imposes a burden on the inspector.
Moreover, since such information as to whether pictures useful for the diagnosis have been collected cannot be obtained, effective diagnosis cannot be conducted and more time is required for the diagnosis.
Furthermore, if movements of ultrasonic pictures of the heart are analyzed on various points of the heart, they are considered beneficial to the various diagnoses of cardiac functions. To this end, if movement states of respective parts can be tracked by extracting contours of the pictures, states of functions of the parts of the heart can be properly grasped and more beneficial diagnosis can be expected.
However, according to the conventional method of displaying contours of the heart obtained as ultrasonic pictures, the extracted contours are merely superimposed over original pictures or displayed completely differently. Due to this, it is difficult to determine whether the extracted contours are correct or not and it is therefore impossible to track states of movements of various parts of the heart. It goes without saying that the conventional method cannot be applied to the grasp of more detailed states of cardiac functions.
In addition, as software for drawing, coloring and filtering, there is computer graphic software (so-called a draw tool). Using the draw tool on a calculator, it is possible to form a graphic such as a contour manually and to modify, scale and color the manually formed contour. The draw tool, however, lacks functions such as comparison of a target and the picture of the target by superimposing the picture over the target and analysis of time series shape changes. Due to this, the draw tool cannot be applied to the evaluation of the accuracy of the contour extraction result and the analysis of the movement state of the moving target using contour lines of the picture of the target as described above.
It is therefore an object of the present invention to provide an ultrasonic picture processing method and an ultrasonic picture processing apparatus capable of determining and collecting pictures which are important to the diagnosis of a disease and are not affected by the movement of the subject's body or the movement of inspector's hands, from ultrasonic pictures obtained by the ultrasonic diagnosis apparatus.
It is also another object of the present invention to provide an ultrasonic picture processing method and an ultrasonic picture processing apparatus capable of easily determining whether extracted contours are correct, capable of tracking and analyzing movement states of various parts from the extracted contour information and capable of making use of the result for a diagnosis.
It is another object of the present invention to provide a picture processing apparatus and a picture processing method capable of automatically calculating a terminal diastole period area or volume and a terminal systole period area or volume, capable of lessening a burden to the inspector and capable of obtaining an objective, accurate inspection result.
It is another object of the present invention to provide a cardiac function analysis support apparatus and a cardiac function analysis support method of precisely associating cardiac wall contours in various time phases to allow information calculated from contour information to be displayed in the form which can be easily evaluated and thereby allow local movement states of the cardiac wall to be easily evaluated.